Due to an increasing number of wireless devices and a growing demand for wireless services, wireless communication systems continue to expand and its applications continue to grow. To meet the growing demand, and to increase interoperability and reduce costs, various sets of standards have been introduced for wireless communications. As an example, one them is Institute of Electrical and Electronics Engineers, Inc. (“IEEE”) 802. IEEE 802includes a family of standards applicable to local area networks (“LAN”) and metropolitan area networks (“MAN”). Within IEEE 802, IEEE 802.16includes a series of wireless broadband standards, commonly referred to as WiMAX™.
The transmission of data, which may include voice, images, video, messages, and other forms of data, in a wireless communication system may be affected by channel conditions, which may vary over time. Good channel conditions may allow a higher rate of modulation and coding, resulting in faster data transmission. In contrast, poor channel conditions can only provide slower data transmission. In many applications, poor channel conditions may require more robust modulation and coding to compensate for a higher likelihood of transmission errors, resulting in additional signaling cost and/or further reduced data transmission rate.
Various factors may constrain the data transmission of wireless communication system. For example, because there are a limited number of wireless channels to serve multiple user terminals, such as mobile stations (“MSs”), radio resource allocation may constrain how or when a mobile station or transmitting terminal, such as a base station (“BS”), can transmit or receive data. Another example is the limited power of MSs, which typically operates on battery power. Power consumption therefore may constrain how or when the MS can transmit or receive data.
One proposal for addressing some of these system constraints include employing a power-saving mode, which gives wireless nodes with better channel conditions priority to transmit data. For example, Lee, J.; Rosenberg, C.; Chong, and E. K. P. discussed the idea in an article titled “An opportunistic power-saving mode and scheduler design for wireless local area networks,” Wireless Communications and Networking Conference, 2006. IEEE, vol. 2, pp. 926-33. However, the use of power-saving mode or other implementations may vary depending on factors such as system applications, system design, user demand, and type of data transmitted.
Therefore, it may be desirable to have systems or methods that provide data communications and can, in some applications, overcome one or more of the problems discussed above.